/Engine/Plugins/Online/OnlineSubsystemUtils/Source/OnlineSubsystemUtils/Classes/OnlineSessionClient.h
Join a session of a given name after potentially tearing down an existing one
virtual void JoinSession ( [FName](API\Runtime\Core\UObject\FName) SessionName, const [FOnlineSessionSearchResult](API\Plugins\OnlineSubsystem\FOnlineSessionSearchResult) & SearchResult )